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$ curl repovive.com/roadmaps/greedy-algorithms/practice-problems/wiggle-subsequence-implementation

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$ curl repovive.com/roadmaps/greedy-algorithms/practice-problems/wiggle-subsequence-implementation

Repovive

Wiggle Subsequence - Implementation - Practice Problems | Greedy Algorithms | Repovive

Repovive.

Greedy Algorithms8 sections · 317 units14h total

Open in Course

Wiggle Subsequence - Implementation

The code

Here is the solution:

function wiggleMaxLength(nums)
 if length <= 1 then
 return length
 up := 1
 down := 1
 for i from 1 to length - 1
 if nums[i] > nums[i-1] then
 up := down + 1
 else if nums[i] < nums[i-1] then
 down := up + 1
 return max(up, down)

Time: $O(n)$ . Space: $O(1)$ .

$up$ = length of longest wiggle ending with an up move. $down$ = ending with down move. Each move extends the opposite direction.